At this point, you likely know the drill. Every election cycle, Big Oil pays into campaigns heftily in order to try to curry favors and influence in Washington, and the Senate is not immune to this fact. Unfortunately the figures surrounding those Senators who have signed this latest letter once again show that these investments pay dividends in the halls of Congress.

As this is a (tar sands) oil pipeline, after all, it also makes sense to dig deeper and look at Big Oil contributions in isolation. Unfortunately, looking at these contributions only makes the picture even clearer.

On average, those Senators who signed the latest letter have received roughly $434,393 from oil interests in their careers since 1999.

Meanwhile, Senators who had the sense to stay off the pro-Keystone XL letter only average $165,968 in lifetime contributions from oil interests.

That amounts to an impressive 262% more in contributions from oil companies to those Senators supporting the Keystone XL tar sands pipeline than those that did not sign the letter.

No matter how you look at it, it’s clear whose interests these Senators are looking out for in sending letters to the Obama Administration in support of a dangerous pipeline that would threaten our communities and climate in order to send dirty oil overseas.

Secretary Kerry spent a career in the Senate pushing for policies that address climate change and protect the environment. He must stand firm in those principles by rejecting the Keystone XL, and listen to the people and not Big Oil.

Note: The figures used, taken from Oil Change International’s Dirty Energy Money database, include contribution amounts for currently sitting Senators in the 113th Congress. These contribution totals are likely lower than reality, as data for some freshman Senators is not yet fully available.